Medical emergency personnel and laymen with minimal training all assist people experiencing a medical emergency. Whether professionals or minimally trained bystanders, those arriving on scene to assist typically have little or no knowledge of the patient's medical background. They are forced to rely on answers provided by the person in distress (when possible) or family, friends, acquaintances, or co-workers.
While some people with chronic illnesses have home monitoring systems and are registered with emergency healthcare providers who know about their medical background, there remain problems. For example, when a person leaves their house and experiences an emergency, it is rare that the healthcare provider is contacted and/or provides the necessary medical information to those who arrive at the emergency scene.
There exist projects where a patient's hospital medical record is provided to the ambulance crew responding on scene. This is certainly an improvement but still does not solve the following problems:                1) First responders on the scene prior to the arrival of the ambulance have no information about the patient; and        2) Even if such medical records were to be provided to the first responders, there is the issue of privacy. Much of the information in the patient's records need not or should not be revealed to more than the minimum number of people.        3) Providing too much information, such as the patient's entire medical record, swamps the emergency responders with too much information making it of little use.        
There exist solutions that manage access to different portions of a patient's medical record. However, such assess is generally a static definition based on a healthcare provider's role.